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31.
Maria Rosaria Melis Salvatora Succu Umberto Iannucci A. Argiolas 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(5):595-600
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection
and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus
of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented
dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine
of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented
apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In
contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results
confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine
and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity
of nitric oxide in the paraventricular nucleus of the hypothalamus.
Received: 30 September 1996 / Accepted: 24 January 1997 相似文献
32.
Cardillo C Mores N Campia U Musumeci V Motolese M Folli G 《American journal of therapeutics》1994,1(3):198-205
The current study analyzed the effects of different doses of the calcium channel blocker felodipine on cardiovascular response to a set of standardized laboratory tasks. We randomly allocated 21 essential hypertensive patients to receive extended release felodipine 5 mg, felodipine 10 mg and placebo, each given once daily for 2 weeks, according to a double-blind 3-period design. At the end of each treatment period, patients were examined at resting baseline and while performing a mental arithmetic test, a handgrip test and a cycle ergometry test. Compared to placebo, the average fall in resting blood pressure (BP) was of 7.9 ± 5.6/6.1 ± 4.5 mm Hg with felodipine 5 mg (p < 0.01) and of 15.1 ± 5.8/13.9 ± 4.5 mm Hg with felodipine 10 mg (p < 0.001). During mental arithmetic, BP decrease was 11.6 ± 8.1/9 ± 5 mm Hg with felodipine 5 mg (p < 0.01) and 20.4 ± 8.1/15.3 ± 5 mm Hg with felodipine 10 mg (p < 0.001). During handgrip test, BP was significantly reduced after both felodipine doses by 11.7 ± 9.3/9.5 ± 6.5 mm Hg (p < 0.05) and 22.1 ± 9.3/22.4 ± 6.5 mm Hg (p < 0.001), respectively. During cycle ergometry, systolic BP was significantly reduced after felodipine 10 mg by 20.1 ± 9.4 mm Hg (p < 0.001), whereas the fall induced by felodipine 5 mg (7.7 ± 9.4 mm Hg) was not statistically significant (p > 0.05); diastolic BP was significantly reduced by both felodipine doses [average fall of 6.6 ± 5.8 mm Hg (p < 0.05) after felodipine 5 mg and of 12.7 ± 5.8 mm Hg (p < 0.001) after felodipine 10 mg]. There was no treatment effect on the magnitude of systolic BP reactivity from baseline during either mental arithmetic, handgrip test or cycle ergometry (all, p > 0.05). Heart rate values were significantly higher after both felodipine doses than after placebo, either at rest or during stress testing (all, p < 0.05). These data suggest that felodipine, especially at higher doses, may be effective in lowering BP not only at rest but also during exposure to commonly recurring stressful situations. 相似文献
33.
The locomotor activity of C57B1/6J and DBA/2J mice was studied, under the influences of heroin, amphetamine, strychnine, or ethanol, and of combinations of the opiate with each one of the other drugs. Heroin treatment was followed by the typical running fit in the C57 mice, while the DBA strain was unaffected. Amphetamine enhanced the activity in the C57 strain only. The combination of heroin with amphetamine or ethanol increased the locomotor activity only in the DBA strain, while heroin + strychnine exerted a clear stimulating effect on the activity of the C57 mice. The strychnine + heroin mixture was more toxic than heroin alone when the lethal doses (LD50) were determined in the 2 strains. 相似文献
34.
Guglielmo Nasti Renato Talamini Andrea Antinori Ferdinando Martellotta Gaia Jacchetti Francesco Chiodo Giuseppe Ballardini Laura Stoppini Giovanni Di Perri Maurizio Mena Marcello Tavio Emanuela Vaccher Antonella D'Arminio Monforte Umberto Tirelli 《Journal of clinical oncology》2003,21(15):2876-2882
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1). 相似文献
35.
Franca Formelli Tiziana Camerini Elena Cavadini Valentina Appierto Maria Grazia Villani Alberto Costa Giuseppe De Palo Maria Gaetana Di Mauro Umberto Veronesi 《Cancer epidemiology, biomarkers & prevention》2003,12(1):34-41
OBJECTIVES: To assess, in women participating in a breast cancer prevention trialon fenretinide (4-HPR), the relationship of drug and retinol levels with the risk of second breast malignancy, taking into account age and menopausal status. METHODS: In a multicenter prevention trial, women with early breast cancer were randomly assigned to receive no treatment or 200 mg of 4-HPR/day for 5 years. Blood was collected at baseline and on a yearly basis during intervention from women recruited at the Istituto Tumori (Milan, Italy; 818 and 756 in the 4-HPR and control arm, respectively, who accounted for 53% of the participants in the trial). The plasma concentrations of 4-HPR, its main metabolite N-(4-methoxyphenyl) retinamide, and retinol were assayed by high-performance liquid chromatography. Three age ranges (or=56 years), menopausal status at baseline, and disease outcome at a median follow-up of 97 months were taken into account in the analysis. RESULTS: Baseline retinol levels were significantly lower (P or=46 years versus or= 0.71; P 相似文献
36.
Santarossa Sandra Vaccher Emanuela Balestreri Luca Volpe Rachele Tirelli Umberto 《Journal of neuro-oncology》1997,35(2):141-143
Patients with locally advanced transitional cell carcinoma (TCC)of the bladder are at high risk forsystemic relapse, with liver, bone and lung beingthe commonest sites of metastases.We report the case of a 52-year-old womanwith a solitary meningeal relapse, a rare siteof recurrence, after 8 months of complete remissionobtained with M-VEC for locally advanced TCC ofthe bladder. We speculate on the likely riskfactors related to this unusual site of recurrence. 相似文献
37.
G Nigro E Sali M M Anceschi M Mazzocco L Maranghi A Clerico M A Castello 《The journal of maternal-fetal & neonatal medicine》2004,15(5):325-329
We report on an infant with multi-system disease including liver fibrosis, right microphthalmia with cataract, interstitial pneumonitis, and hyperechoic lesions in the basal ganglia and in the periventricular and thalamic regions. Prenatal ascites with hepatomegaly concomitantly with detection of cytomegalovirus (CMV) DNA in the amniotic fluid, following recurrent maternal CMV infection, had been shown. Although CMV culture and DNA detection were negative in the urine, the infant was given foscarnet because CMV infection was demonstrated in the liver by DNA detection and immunohistochemical staining. Favorable clinical outcome and absence of CMV in the liver were subsequently shown. Our case suggests that congenital CMV disease following maternal recurrence may not be associated with disseminated infection but only with intracellular infection. The diagnosis should therefore be based on CMV detection in the involved organs. Moreover, this is the first report on the possible efficacy and safety of foscarnet for therapy of immunocompetent infants with congenital CMV disease. 相似文献
38.
Comparison between two antimicrobial protocols with or without guided bone regeneration in the treatment of peri‐implantitis. A histomorphometric study in dogs 下载免费PDF全文
39.
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